feat!: Add pagination to Enterprise.ListBudgets and add GetUserStatesForBudget (#4408)

[devaniketh]

Fixes #4408

Summary

• Added EnterpriseListBudgetsOptions embedding ListOptions to enable pagination (page, per_page) in EnterpriseService.ListBudgets.
• Added EnterpriseService.GetUserStatesForBudget along with EnterpriseBudgetUserState, EnterpriseBudgetUserStates, and EnterpriseGetUserStatesOptions for endpoint GET /enterprises/{enterprise}/settings/billing/budgets/{budget_id}/user-states.
• Regenerated accessors, iterators (ListBudgetsIter), and stringifier test fixtures via script/generate.sh.
• Added full unit test coverage in enterprise_budgets_test.go.

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[codecov]

Codecov Report

❌ Patch coverage is 94.28571% with 2 lines in your changes missing coverage. Please review.
✅ Project coverage is 98.52%. Comparing base (6d624b5) to head (c0102b1).

Files with missing lines	Patch %	Lines
github/enterprise_budgets.go	88.23%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #4501      +/-   ##
==========================================
- Coverage   98.53%   98.52%   -0.01%     
==========================================
  Files         195      195              
  Lines       17763    17798      +35     
==========================================
+ Hits        17502    17535      +33     
- Misses        261      263       +2     

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[Not-Dhananjay-Mishra]

This endpoint has a few other query parameters as well.
Let’s create a new ListBudgetsOptions struct for it

type ListBudgetsOptions struct {
	Scope string `url:"scope,omitempty"`
	User  string `url:"user,omitempty"`
	ListOptions
}

[Not-Dhananjay-Mishra]

Suggested change

	u := fmt.Sprintf("enterprises/%v/settings/billing/budgets/%v/user-states", enterprise, budgetID)
	u, err := addOptions(u, opts)
	u := fmt.Sprintf("enterprises/%v/settings/billing/budgets/%v/user-states", enterprise, budgetID)
	u, err := addOptions(u, opts)

[Not-Dhananjay-Mishra]

has_next_page and total_count are required field and we don't use ,omitempty with them.

  "required": [
    "user_states",
    "has_next_page",
    "total_count"
  ]

Suggested change

	type EnterpriseBudgetUserStates struct {
	UserStates []*EnterpriseBudgetUserState `json:"user_states"`
	HasNextPage *bool `json:"has_next_page,omitempty"`
	TotalCount *int `json:"total_count,omitempty"`
	}
	type EnterpriseBudgetUserStates struct {
	UserStates []*EnterpriseBudgetUserState `json:"user_states"`
	HasNextPage bool `json:"has_next_page"`
	TotalCount int `json:"total_count"`
	}

[Not-Dhananjay-Mishra]

consumed_amount and target_amount are required.

        "required": [
          "consumed_amount",
          "target_amount"
        ]

Suggested change

	type EnterpriseBudgetUserState struct {
	User *string `json:"user,omitempty"`
	ConsumedAmount *float64 `json:"consumed_amount,omitempty"`
	TargetAmount *float64 `json:"target_amount,omitempty"`
	OverrideBudgetID *string `json:"override_budget_id,omitempty"`
	}
	type EnterpriseBudgetUserState struct {
	User *string `json:"user,omitempty"`
	ConsumedAmount float64 `json:"consumed_amount"`
	TargetAmount float64 `json:"target_amount"`
	OverrideBudgetID *string `json:"override_budget_id,omitempty"`
	}